calling Nemo

Communicating underwater is tough since sound waves travel differently in water than in air. Researchers at the University of Texas at Dallas have discovered that sheets of carbon nanotubes can act as speakers 100x more effectively than they predicted. The carbon nanotubes are very hydrophobic (meaning they don't like water) so there is a very thin layer of air which helps transmit sound. Maybe in the future you can call up a fish for dinner.
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